As digital imaging technology advances rapidly in recent years, various personal hand-held digital terminals (such as digital cameras, camcorders, notebook computer, personal digital assistant and mobile phone, etc) equipped with digital imaging components (such as CCD and CMOS, etc) are introduced to the market constantly. Not only quality of the personal hand-held digital terminals becomes higher, but also their sizes or volumes become less, and their prices become lower gradually. These personal hand-held digital terminals available in the market are getting increasingly popular, and many personal hand-held digital terminals equipped with digital imaging devices also have advanced functions such as auto focus and auto exposure. With the increasing of explosive popularity of the personal hand-held digital terminals equipped with the digital imaging devices in recent years, many designers or manufacturers of the digital imaging devices have dedicated their efforts to provide digital imaging devices capable of taking pictures with good quality since the quality of pictures is not only one of the most essential and important factors for determining whether the digital imaging devices are of good quality, but also is a requisite requirement requested by most ordinary users while purchasing the digital imaging devices.
In general, when an ordinary user uses a digital imaging device, such as a digital camera, to take a picture, he/she usually determines the quality of picture going to be taken through a small LCD of the digital camera by eyes. However, since preview pictures shown on the small LCD are often too small to let the user clearly identify the actual quality of the preview picture, which in turn causes the user to take more times in zooming the preview picture in or out for reviewing and identifying the actual quality of the preview picture carefully. Though lots of new technologies, such as auto anti-shaking technology, auto exposure technology and auto white balance technology, have now been widely implemented in the digital cameras for helping users to take pictures with good quality, problems of causing pictures to be taken by the digital cameras in shaking, blur, backlight, under-exposure, over-exposure or bad white balance status still happened while most users operated the digital cameras in situations beyond the controls of these new technologies, which also led to the result of taking pictures with poor quality. In addition, the poor quality of the pictures is also caused by the detection mechanism of the digital cameras, which is unable to show the above statuses of the preview pictures in a real time or to show whether the digital cameras are operated in situations beyond the controls of these new technologies, and puzzles the user to identify whether the poor quality of the pictures is caused by personal skills or digital cameras. According to research by the inventor herein, the detection mechanism for showing the above comprehensive statuses of the preview pictures on the digital cameras in a real time before taking the pictures hasn't been seen in imaging and image processing application, or embedded in operating systems of the digital cameras or other personal hand-held digital terminals equipped with digital imaging components yet. Hence, there exists a prompt need for creating a new and useful method applied to the digital cameras for detecting and showing the above comprehensive statuses of the pictures on a display of the digital cameras in a real time, so as to enable the user to easily identify the quality of the picture before or after the picture is taken by the digital cameras and to ensure that every picture taken by the digital cameras is in a desired quality.